Arizona ranks in the bottom half of states in four-year graduation rates, according to newly released figures that the U.S. Department of Education says are a better measure of the key academic benchmark than previous years’ figures.

Preliminary data for the 2010-11 school year showed that 78 percent of Arizona students graduated from high school in four years. Graduation rates for Arizona students still learning English were much lower, at only 25 percent, the lowest of any state.

Iowa had the highest overall graduation rate, at 88 percent, while Nevada had the lowest, at 62 percent.

U.S. Department of Education officials said the latest figures are a more accurate snapshot than previous reports because states must report data more uniformly than in the past.

“By using this new measure, states will be more honest in holding schools accountable and ensuring that students succeed,” U.S. Secretary of Education Arne Duncan said in a statement.

A national graduate-rate average was not released on Tuesday, as data for three states — Idaho, Kentucky and Oklahoma — were not yet available.

The previous method of calculating graduation rates was widely criticized by education experts as undercounting dropouts.

Education experts say several factors are to blame for Arizona’s graduation rate, including the high percentage of students who are learning English and a mobile student population, which makes some students difficult to track.

To earn a diploma, Arizona students also must pass a reading, writing and math exam called Arizona’s Instrument to Measure Standards, or AIMS. Some experts blame the state’s below-average funding for education as another reason for the middling showing.

Graduation rates are taking on added importance as the federal government and the states have put in place more accountability measures for public schools.

In Arizona, graduation rates are a factor in a school’s A through F letter grade, although they play a much smaller role than AIMS scores.

More broadly, the percentage of students who graduate from high school can have social and economic impacts for communities and states. National surveys have shown that people who lack high-school diplomas generally have higher unemployment rates and earn less money over their lifetimes. High-school graduates are less likely to commit crimes or rely on public services such as government health care, food stamps or housing assistance, according to a 2005 study by researchers at Columbia University.

Arizona’s graduation rates have historically lagged the national average.

Over the last five years, the rate ranged from 73 to 76 percent, according to the Arizona Department of Education. While the 2011 rate is about 3 percent higher than the previous year, the U.S. Department of Education said the latest rate can’t be compared with previous years because the methodology for calculating the rate is different.

State Superintendent of Public Instruction John Huppenthal was unavailable for comment Tuesday.

Education experts are especially concerned with the state’s low graduation rate for students learning English.

Only one in four English-language learners graduated within four years. These students are required by the state to take four hours of English instruction a day, which educators say leaves less time to earn the 22 credits required for graduation.

Even if they have enough credits, students also need to pass the math, reading and writing parts of the state-mandated AIMS to get a diploma.

Fateme Yazdani, a senior at Central High School in Phoenix, was born in Afghanistan and grew up in Iran and Turkey. The 21-year-old speaks Persian and has been in the United States since 2010.

She knew very little English when she moved to the country and has been taking night classes and summer school to accumulate enough credits toward graduation. She will have enough credits by May but still needs to pass the reading and writing portions of the AIMS exam.

“If I’m not going to graduate, that will hurt me,” said Yazdani, who wants to go to college.

Craig Pletenik, a spokesman for the Phoenix Union High School District, said the requirement for four hours of English daily, coupled with passing the AIMS test, is a challenge for students who speak another language and have recently moved to the United States. That’s why the four-year graduation rates can be deceptive, he said. Some of the students will graduate; they just need more time.

“We have a lot of students who are five-year graduates,” he said.

Craig Barrett, chairman of Arizona Ready, a group that seeks to prepare students for success in college and careers, said he was not surprised by Arizona’s low graduation rate.

“Until we make education relevant to kids who are dropping out, we will have this problem,” he said.

Barrett said money needs to be redirected to more Career Technical Education programs where students can learn material directly related to a profession.

“Teach them the math they need to know to be an auto-mechanic or contractor, for example, and they will stay engaged, interested and graduate,” he said.

Rosemary Papa, an education professor at Northern Arizona University, attributed the low graduation rates to a lack of education funding. Schools need more money, she said, to hire additional quality math teachers because high-school students now need four years of math to graduate, up from three years last year.

Schools also need to have enough teachers on staff so they can do aggressive interventions with students who aren’t grasping a concept.

She predicts that without additional resources, the state’s graduation rates are going to get worse, especially with the four-year math requirement.

12 News reporter Kim Covington contributed to this article. Reach the reporter at 602-444-8072 or anne.ryman@arizonarepublic.com.

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